1. Field of the Invention
This invention relates to an electronic still camera and more particularly to a digital electronic still camera in which video signals representative of a still image or scene are stored in the form of digital data in a memory.
2. Description of the Prior Art
In an electronic still camera disclosed for example in the Japanese Patent Laid-Open Publication No. 183592/1984, a memory is detachably connected to the main body of the camera which includes an optical imaging system and a solid state imaging device. Video signals representing the still image or scene imaged by the imaging device are stored in the memory in the form of digital signals. The memory, with the video signals stored therein is detached from the electronic still camera and loaded into a playback unit. The video signals read out from the memory by the playback unit are reproduced as a visual image on a screen of a video monitor.
The solid state imaging devices mounted on the camera, in general, have an array of color filter segments and spectral transmittivities that are proper to the specific imaging devices. Thus, various combinations of pixels are employed, such as the combinations of pixels of cyan (Cy), magenta (M), yellow (Ye) and green (G); red (R), green (G) and blue (B); or cyan (Cy), white (W), yellow (Ye) and green (G). In certain imaging devices, the pixels in a line are different in color from pixel to pixel, while in others, the pixels of the same color are arrayed in the perpendicular direction of a screen.
In the above noted Japanese Patent Laid-Open Publication, color separation data concerning the pixel array and spectral properties of the solid state imaging device, which is mounted on the camera, are stored in the memory in the form of codes along with the video signals each time a scene is shot by the camera. For proper color separation of the video signals, the playback unit has a series of color separation processing programs for handling a variety of the solid state imaging devices. This is in consideration that, unless the relative disposition between the pixel array of the photosensitive cells and the filter, segment array of the color filter or the phasing relation between the drive timing of the imaging device and the analog to digital converter and the timing of data writing into the memory are determined appropriately, pixel signals of the correct color cannot be reproduced upon reproducing the video signals by the playback unit. Thus, in the above noted Japanese Patent Laid-Open Publication, an occasionally suitable color separation processing program is accessed on the basis of the color separation data or information for the image at the time the video signals are read out and reproduced from the memory, and the operation of color separation is carried out in accordance with the thus selected processing program.
However, there are a number of different kinds of imaging devices and, in order that the playback unit be so designed that the video signals imaged by the different kinds of the digital electronic still cameras employing a specific imaging device may be reproduced correctly, the color separation processing programs need be stored in the memory of the playback unit in association with these different imaging devices. With the provision of a series of different color separation processing programs, the memory capacity of the playback unit is necessarily increased with increase in complexity of the system, and increased costs. In view of increasing variations in the imaging devices, it would be more and more difficult to handle them properly in the playback system.